/**
 *  @(#)  IFAAAuthenticator  module    1.0  2017/03/24
 *
 *  Copyright  (c)  2017,  IFAA  and/or  its  affiliates.  All  rights  reserved.
 *
 *  Redistribution  and  use  in  source  and  binary  forms,  with  or  without
 *  modification,  are  permitted  provided  that  the  following  conditions  are  met:
 *
 *  -Redistribution  of  source  code  must  retain  the  above  copyright  notice,  this
 *    list  of  conditions  and  the  following  disclaimer.
 *
 *  -Redistribution  in  binary  form  must  reproduce  the  above  copyright  notice,
 *    this  list  of  conditions  and  the  following  disclaimer  in  the  documentation
 *    and/or  other  materials  provided  with  the  distribution.
 *
 *  Neither  the  name  of  IFAA  or  the  names  of  contributors  may
 *  be  used  to  endorse  or  promote  products  derived  from  this  software  without
 *  specific  prior  written  permission.
 *
 *  This  software  is  provided  "AS  IS,"  without  a  warranty  of  any  kind.  ALL
 *  EXPRESS  OR  IMPLIED  CONDITIONS,  REPRESENTATIONS  AND  WARRANTIES,  INCLUDING
 *  ANY  IMPLIED  WARRANTY  OF  MERCHANTABILITY,  FITNESS  FOR  A  PARTICULAR  PURPOSE
 *  OR  NON-INFRINGEMENT,  ARE  HEREBY  EXCLUDED.  IFAA,  ORG.
 *  AND  ITS  LICENSORS  SHALL  NOT  BE  LIABLE  FOR  ANY  DAMAGES  SUFFERED  BY  LICENSEE
 *  AS  A  RESULT  OF  USING,  MODIFYING  OR  DISTRIBUTING  THIS  SOFTWARE  OR  ITS
 *  DERIVATIVES.  IN  NO  EVENT  WILL  IFAA  OR  ITS  LICENSORS  BE  LIABLE  FOR  ANY  LOST
 *  REVENUE,  PROFIT  OR  DATA,  OR  FOR  DIRECT,  INDIRECT,  SPECIAL,  CONSEQUENTIAL,
 *  INCIDENTAL  OR  PUNITIVE  DAMAGES,  HOWEVER  CAUSED  AND  REGARDLESS  OF  THE  THEORY
 *  OF  LIABILITY,  ARISING  OUT  OF  THE  USE  OF  OR  INABILITY  TO  USE  THIS  SOFTWARE,
 *  EVEN  IF  IFAA  HAS  BEEN  ADVISED  OF  THE  POSSIBILITY  OF  SUCH  DAMAGES.
 *
 *  You  acknowledge  that  this  software  is  not  designed,  licensed  or  intended
 *  for  use  in  the  design,  construction,  operation  or  maintenance  of  any
 *  nuclear  facility.
 *
 */
package com.ifaa.sdk.authenticatorservice.fingerprint.util;

import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;
import java.security.cert.CertificateFactory;

import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;

import com.ifaa.sdk.auth.AuthenticatorLOG;

import android.util.Log;

/**
 * 
 * @author qiyi.wxc
 * @version 1.0
 */
public class PackageUtils {

    /**
     * get the base64url(sha1(apk.cert)).replace("=", "");
     * 
     * @param context
     * @param appName
     * @return
     * @throws NameNotFoundException 
     * @throws CertificateException 
     * @throws NoSuchAlgorithmException 
     */
    public static byte[] getApkKeyHashBytes(Context context, String appName)
                                                                            throws NameNotFoundException,
                                                                            CertificateException,
                                                                            NoSuchAlgorithmException {
        PackageManager pm = context.getPackageManager();
        PackageInfo packageInfo = null;
        packageInfo = pm.getPackageInfo(appName, PackageManager.GET_SIGNATURES);
        android.content.pm.Signature[] signatures = packageInfo.signatures;
        byte[] signature = signatures[0].toByteArray();
        InputStream input = new ByteArrayInputStream(signature);
        CertificateFactory cf = null;
        cf = CertificateFactory.getInstance("X509");
        byte[] certData = cf.generateCertificate(input).getEncoded();
        MessageDigest messageDigest = MessageDigest.getInstance("SHA-1");
        messageDigest.update(certData);
        byte[] resultByte = messageDigest.digest();
        return resultByte;
    }
}
